1. Field of the Invention
This invention relates to a facsimile device or apparatus which has an image memory for storing received image data and/or image data to be sent.
2. Description of the Related Art
Many conventional laser facsimile apparatus which print received images by means of a laser beam store the images on a page-by-page basis. These facsimile apparatus are generally equipped with an exclusive printing memory for storing a bitmap image of one page to be printed at the highest resolution. Some facsimile apparatus have a memory sending function for initially coding and temporarily storing image data in a memory and then later sending the image data at the specified time, and a backup receiving function for temporarily storing received coded image data in a memory when the apparatus is out of print paper. These facsimile apparatus are equipped with a communication memory separately from the printing memory.
In an image printing processor, an image is developed into a bitmap, with the resolution of the image data varied depending on the remaining memory capacity if the bitmap's size is greater than the usable area of the image printing memory, so that no part of image data is lost. Such an image printing processor is disclosed in U.S. Pat. No. 5,068,805 and Japanese Unexamined Patent Publication Nos. 4-62169 and 4-152457.
In the above-mentioned case of a facsimile apparatus having a printing memory and a communication memory, the printing memory needs a capacity sufficient to store the bitmap image data of one page at the highest resolution. This thus necessitates providing a large total memory capacity, and the facsimile apparatus is therefore expensive. Additionally, the printing memory is used exclusively for printing, and therefore is not used efficiently. For example, it is not possible for the communication function, when it needs additional memory area, to have an unused area of the printing memory allocated to the communication memory. In case the capacity of the communication memory is small, the memory sending function and backup receiving function are unfavorably limited in the quantity of transacted data.